DE2052896A1 - Cutting device - Google Patents

Description

D - 24 LÜBECK. WIDE STREET 52-54

October 27, 1970 Applicant: Cz./Sch.

Caplin Engineering Company Limited, Ipswich (Suffolk), Hadleigh Road, Elton Park Works, England

The present invention relates to a machine tool, e.g. a machine tool for cutting workpieces, e.g. of silicon or the like, in a number of slices or wafers, plates or the like. of a predetermined thickness.

In particular, the invention relates to a machine tool in which the cutting device comprises a circular saw blade or a cutter in the form of a toroidal spool or ring which has a cutting surface formed on its inner periphery and which or which is attached with her or its outer edge or outer circumference to a cutting support member, which is a chuck or the like. includes which is rotatably mounted in order to be able to set the saw blade in rotation. The machine tool includes a feed mechanism which is adapted to receive the workpiece and, when the tool is operated, can adjust the workpiece in the direction of the plane of the saw blade and furthermore the works flow in the direction of and we, τ from the cutting surface; el «:; ? Ά \ * <\ -

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■ f lij. k · Μ- »Ι) / MW, frunl: Ur. H. WiHiMi, O.-ji (0 «':.'' IH Dipl.-tng. Th Wllriren Iflbn-k- , H-Ij I ■ ι 59

ORIGINAL INSPECTED

2052898

sheet can move to the workpiece repeatedly or multiple times to be able to share. Such a tool will hereinafter be referred to by the term "machine tool of the type described" taken·

According to one aspect of the invention, a machine tool of the type described is provided in which the cutting support or the cutting support member for the purpose of rotation In a FlÜsslg-

■ ■ -.

j keitslagerung, eg in air bearings or air-lubricated ι
Bearings, arranged 1st. Preferably at least some of the cooperating bearing surfaces of the bearings are conical in shape.

In one embodiment there is the cutting support or the chuck rotatable about a generally vertical axis, and the advancement mechanism includes an arm which is arranged for the purpose of oscillating movement about a generally vertical axis, about said repetitive reciprocating to generate accompanying feed movement. The oscillating arm can be adapted to the orientation of the workpiece relative to the plane of the saw blade - to allow it.

For a better understanding, the invention is below under Explained in more detail with reference to the accompanying drawings. En cells:

Ί Ί

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Figure 1 is a perspective view of the head of the machine tool of the type described according to one embodiment of the invention, wherein some parts are shown in section,

FIG. 2 is a side view of the head according to FIG. 1, with some parts also in section are shown

Fig. 3 is a view of the head in the direction of arrow A in Fig. 1,

Fig. H is a plan view of the head,

Fig. 5 shows, on an enlarged scale, an axial section of the Air licensed warehouse and son support or the chuck of the head according to the Flg. 1 to 4, where the horizontal axis of rotation of the cutting support or the chuck was placed horizontally for the sake of simplicity,

6 schematically shows a safety circuit for preventing damage to the air-lubricated bearing, if the compressed air supply to the warehouse should fail.

According to FIGS. 1 to 4, the machine has a main frame, which is indicated figuratively at 1, which carries a horizontal bearing plate 2. Supported by supports 3 from the bearing plate is a chuck carrier k _s in which a ring bearing chuck 5 is attached. Each support 3 is composed of separate upper and lower parts 3a and 3b, the adjacent ends of which are formed with different thread slopes which extend into a nut 3c. By rotating the nut 3c relative to the parts, the length of the supports 3 can be finely adjusted in order to correct the alignment of the chuck carrier 4 and thus that of the chuck 5. The chuck 5 is rotatable about a generally vertical axis in an air-lubricated laser, the bearing generally with

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is indicated.

As shown in detail in Fig. 5, the chuck closes an axially extending, generally cylindrical portion 7 a, whose circumferentially continuous outer surface after! diverges below and generally frustoconical in shape having. The chuck further includes a clamping ring 9, which is attached to the upper end of the cylindrical part 7 by screws is attached and has a horizontal surface 11 lying below. The surfaces 8 and 11 form the bearing surfaces of the rotatable element of the air-ventilated bearing and form

together form a radially outwardly open annular recess.

The chuck carrier 4 is provided with a circular opening, formed by surface 12 and diverging downward and generally frustoconical in shape. At the upper end of the surface 12 ..- is a horizontally extending, overhead annular surface 13. The surfaces 12 and 13 form the bearing surfaces of the static element of the air-thrown bearing and together form an annular one Shoulder extending radially into the annular recess, the bearing surfaces 12 and 13 correspondingly with the Storage areas 8 and 11 work together.

The shoulder is provided with a plurality of circumferentially distributed slots 14 which define the annular space 15 in the apex connect the shoulder with the atmosphere. The shoulder is welter

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with a large number of circumferentially distributed sentences

Mistake
Slots 16 and 17 £ ~ we: e ⁿ ic in accordance with the bearing surfaces 13 and open out and alternate in the direction of circumferential with the slots Ik. Both sets of slots 16 and 17 communicate with an annular charging conduit 18 sealed by a ring 19 and resilient sealing rings 20, the conduit 18 communicating with one or more inlets 22 via one or more axially extending passageways 21, the Inlets are connected to a source of compressed air (not shown).

The working cycle between the opposite inclined bearing surfaces 12 and 8 and between the opposite horizontal bearing surfaces 13 and 11 is now critical in a range from 0.0381 mm to 0.0203. In a preferred embodiment, the clearance is on the order of 0.0279 mm, although it is exaggerated in FIG. 5 for the sake of clarity. Although the bearing surfaces 12 and 8 are inclined, the game can still be precisely obtained in a simple manner, namely ^; H first by machining, lapping or the like, whereby these surfaces are brought as close as possible to the desired final dimensions, and then by machining or the like, whereby one or both bearing surfaces 11 or 11 are formed, if necessary is to reduce the play or alternatively by machining or the like., whereby one or both of the clamped horizontal surfaces of the clamping

lining ring 9 and the cylindrical part 7 adjoining the screws 10, in the annular zone radially inward of the

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Bearing surfaces 11 and 13 is formed when it is necessary to reduce the play. ,

The air-lubricated bearing works as follows:

When pressurized air is introduced into charge line 18 through inlets 22, the air flows continuously through slots 16 and 17 into the spaces between opposing bearing surfaces 8 and 12 and 11 and 13, respectively. A proportion of this air flows inwardly into the annular space 15, from where it is discharged into the atmosphere via the slots 1 * 1, while another proportion of the slots 16 and 17 flows in opposite directions and further through the annular gaps of the lower ends of the surfaces 8 and and correspondingly through the radially outer ends of surfaces 11 and 13 emanates into the atmosphere. In this state, the chuck floats in the air or is carried by the air flowing through between said opposing bearing surfaces, the chuck being rotatable relative to the chuck carrier h without contacting the bearing surface.

Due to the particular inclination of the opposing bearing surfaces 8 and 12, the upward axial movement and the radial movement of the chuck 5 is minimized relative to the chuck member ¹ I or prevented. The opposite bearing surfaces 11 and 13 minimize or prevent the downward movement of the chuck; chuck 5 according to the weight of the chuck, since, as is clear from FIGS.

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kai extending axis of rotation is mounted at the top, i.e., 5 at the right end of the chuck. The pressure of Air flowing in through the slots 16 is in this embodiment the same as that flowing in through the slots 17. For example, in this particular embodiment, in which the air bearings are approximately thirteen inches in diameter, so that the chuck is such; Size to accommodate saw blades of up to approximately seventeen inches in outer diameter, the air pressure, flowing in through inlets 22 are on the order of 5.6 kgf / cm to 7.0 kgf / cm.

The chuck 5 may be by any suitable drive in turn be placed, for example, the outer wall 23 are of the putter driven by a belt 24 of the cylindrical portion 7 of the licensing with a variable speed electric motor is connected, which in outline at 25 in Fig. * i is indicated. The chuck may at a speed in the range of ^1500-1 IOOO Uradrehungdh per minute in revolution offset W may be, for example, at 3500 revolutions per minute.

As can be seen from Fig. 5, a cross-sectionally L-shaped ring 26 is fastened by screws 27 to the upper surface of the chuck ring 9, on which a pair of saw blade clamping rings 28, 29 are axially slidably mounted. The rings 28,29 are connected to one another by screws 30 and to the L-shaped ring 26 by screws 31. This makes it clear that the rings 28,29 1 η reference

1 09819/1

axially displaced on the L-ring 26 and adjusted by screws 31 can be. When using the chuck 5 is an annular saw blade 32 through its outer periphery between pinched the rings 28,29. The inner peripheral surface 32a forms the cutting edge of the blade and for this purpose may comprise a diamond-tipped surface. The radial tension of the The blade can be changed by adjusting the screws 31, this action causes the saw blade to engage and be altered by the conical top edge or the conical upper edge 26a of the ring 26. By replacing the rings 26,28,29 with rings of larger diameters, the chuck can be used in conjunction with saw blades of various sizes, e.g. with saw blades from twelve to sixteen inches in diameter Diameter.

Within the chuck 5 there is mounted a stationary, generally cylindrical inner cover 33a which is attached to the bearing plate 2 and serves to shield the chuck and in particular the air-coated bearing. An outer cover 33b is disposed over the chuck and the chuck ^{carrier ^ and is supported by a frame 3 1} * of the carrier M. The cover 33b and the frame 3 * have been omitted in FIGS. 1 to M for the sake of clarity.

Referring again to FIGS. 1 to k , the machine tool likewise has a feed mechanism, which is designated generally by 35. This mechanism includes an arm 36

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one that is mounted above the chuck 5. One end of the arm 36 is connected via a coupling block 37 to the upper end of a vertical shaft 38 which is rotatably supported in a bearing member 39, the member 39 being supported by the bearing plate 2 and the lower end of the shaft 38 with a lever 40 is connected, which is coupled to a piston which is arranged in the cylinder of a hydraulic double-acting piston device 4l. When the piston device 4l is actuated, the arm 36 is moved back and forth or moved horizontally back and forth over the chuck λ .

As shown in Figures 1 and 2, said end of the arm 36 is rotatable with the coupling block 37 by a horizontal pivot pins 42 connected to allow the arm to be manually lifted and moved away from the chuck can, which can also be done directly by means of a mechanical linkage (not shown) to the chuck to grant access for maintenance or repairs. The arm 36 is also capable of a short distance by means of a hydraulic piston assembly 43 to be able to be raised, the assembly being attached to the arm and coupled to a cam block 44 slidable in a housing. The block has an inclined lower surface 45 that extends on a vertical pin 46 slidably mounted in the arm and on the upper surface of the coupling block 37 rests. When the piston assembly 43 is actuated, the block 44 is displaced horizontally, whereby the pin 46 and thus the arm

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is moved vertically. The lowest or working position of the Arm 36 can be predetermined by an adjusting screw 47, which extends through the arm and also cooperates with block 37. A fine adjustment dial (not shown) can be provided to enable precise adjustment of the arm.

The coupling block 37 and thus the arm can be rotated or pivoted connected to the upper end of shaft 38 by a horizontal pivot pin 48 which is at right angles to the pin 42 is arranged, and the axis of the pivot pin 48 coincides with the plane of the saw blade and also with its radius. A manual control knob 49 and a fine adjustment dial 50 are provided, due to which the alignment of the arm 36 about this axis can be set precisely. The other end of the arm 36 carries a fixed erected plate 51, and a movable plate 52 is fixed to the plate 51 so that the plate 52 and so that the workpiece carrier 53, which is rigidly attached to the plate 52, can be aligned about a projected axis, which with the plane of the saw blade and the normal to the axis of the pivot pin 48 coincide. In this regard, the plate 51 is with a pair of arcuate slots 51a in which pieces 52a are slidably disposed, the pieces 52a on the Plate 52 are attached. A manually operable fine tuning tuner 52b is provided which enables the alignment of the platen 52 and thus the carrier 53 can be precisely determined about the projected axis mentioned.

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The workpiece carrier 53 is of a known construction and is therefore not described and illustrated in detail. Basically, the carrier has a vertical feed spindle 5 ^ ₃ which can be rotated in order to be able to move a suspension device 5 * 1 a and a workpiece hanging on it downwards, for example a cylindrical workpiece that includes a rod 55 made of silicon. The rotation of the feed screw 5 ^ is brought about by an adjustment mechanism, which is designated generally by 56. This mechanism, which is also not described in detail,

around is used for the repeatable adjustment of the silicon rod 55, / according to to be able to advance a predetermined, but adjustable distance or amount, whereby the thickness of the disc is determined, which is cut from the bar by the saw blade.

As shown in Figures 1 and 3, a disc removal device, which is generally designated 57, arranged below the plane of the saw blade 32. This facility includes a platform 58 with a vacuum passage 58a and is mounted on an L-shaped lever 59 which rotates about a horizontal axis 60 can be moved back and forth by means of a hydraulic actuating arrangement 6l, namely between a position according to the figures 1 and 3, the position being shown in full lines, and a position according to FIG. 3, this position being shown in phantom is shown.

In the operation of the machine tool, the chuck 5 and the saw blade 32 rotate at the desired speed, and with the silicon rod 55, which is centrally located above the chuck such as

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is arranged, the alignment of the silicon rod 55 around the point of collapse of the plane of the saw blade 32 and its axis of rotation is set on all sides and held by the aforementioned pin setting scales, whereby the plane is determined in which the silicon rod is cut into pieces with respect to its longitudinal axis . The rod is set down or moved from the carrier 53 by a setting or. Moving mechanism 56, namely the rod is moved through the opening in the saw blade by a distance which is determined by the thickness of the pieces to be cut. Ber arm 36 is then pivoted laterally through the piston assembly Hl, to bring the rod to the diamond tipped cutting surface 32a into engagement, is separated to a slice of the rod, which occurs in a position above the disc removal platform 58th A vacuum is then created through passage 58a, causing the severed disc to rest on the platform. The platform is then moved away from its position shown in full lines by the actuator assembly 61 and the vacuum released, allowing the disc to fall off the platform.

The arm 36 and the platform 58 are then returned to their original positions, and during this movement of the cam block HH is to the left in Fig. Displaced by the piston 43 2 to press down about the pin HS and thereby slightly raise the arm 36 to contact with the cut lower end of the rod with your saw blade to avoid this end

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could cut. When this end is over the central opening of the saw blade, the piston 43 is actuated to raise the cam block 44 to the right, whereby the arm returns to its lower position, with the rod a further predetermined Amount is adjusted downwards or set, and this cycle, which can be controlled manually or automatically can, is then repeated.

The machine tool described and illustrated has numerous Advantages. By using an air lubricated bearing or a other liquid bearings instead of a conventional bearing, it is possible to build bearings with a larger diameter, with higher speeds or speeds work, while the axial and radial play of the chuck in the permissible fine Limits can be kept. Since the bearing includes opposing bearing surfaces, e.g., surfaces 8 and 12, which are inclined run conically, these bearing surfaces and the other bearing surfaces, e.g. the bearing surfaces 11 and 13 during manufacture

i Λ position machined or otherwise finished; ^ to produce the desired clearance in the assembled bearing as described above.

Since the feed mechanism includes a pivotably attached arm J> S , the distance between the workpiece and the arm attachment, ie the bearing member 39, remains the same regardless of the pivoted position of the arm, since this distance or the overhang does not change, contrary to the usual Tool-

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leadership, the downward loads that act on the arm do not change depending on the arm position.

Since a failure of the air supply would cause a contact of the respective bearing surfaces for the air bearings during the normal rotation of the chuck and thus damage to the opposite bearing surfaces against each other results from a total or partial placement of the bearing surfaces, a safety circuit is provided such as schematically is shown in FIG. In this circuit a main supply source of ^v omprimierter air, for example, is connected from a compressor 62 via a line 63 with the air bearing 6, and a Notversorgungsquelle for compressed air, which for example is contained in a cylinder 64 and sufficient volume to the air bearing To be able to operate for five to ten minutes is connected to the air bearing 6 via a line 65 . The lines 63 and 65 close both manually operable valves 66, pressure-sensitive electrical switch 67 and one-way or non-return valves 68 ein.Die Notversorgungsleitung contains 65 Welter a normally closed first pressure-sensitive valve 69 which is controlled by the air pressure of the main line, the on to this valve line TO is applied and is only open when the main air pressure is below a predetermined value. Line 65 further includes, between valve 69 and air bearing 6, a second pressure sensitive valve 71, the purpose of which is to isolate the emergency supply air supply from bearing 6 when the machine is not in use, regardless of the pressure in the main line supply, to weaken the

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J '■■■■ ■■ ■ ■■ ■ ■ · ■ ■■ ■ ■

- 15 emergency air supply to avoid.

The valve 71 shown schematically includes a spool 71a which is actuated by a piston 71b to selectively connect five valve ports together. The slide and piston are biased on one side by a spring 72, namely from an open position (representation of the piston in dashed lines), in which connections, represented by dashed lines 73a, are established, to a closed position (representation of the piston in full lines), in which connections, represented by solid lines 73b, are made. A line 7 ¹ I connects the line 63 to the actuating cylinder 71c via a solenoid operated valve 75 which is adapted to be opened when energized and which is connected to the power circuit (not shown) of the chuck drive motor 25 (Pig the cylinder 71c is connected to one of the valve ports by a bypass line 76. One line connects the line 63 to another valve port via a check valve 78 and another solenoid operated valve 79, ([which is adapted to be closed instantly when it is by a Pulse is excited due to the "stop" control of the chuck drive motor 25. A secondary line 80 connects the common connection of the valves 78 and 79 to the inflow side of the valve 69.

When it is desired to start the machine, the main supply and emergency supply air sources are through

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I - 16 -

opening the taps 66 switched on. When the emergency supply source

'' is switched on before the main supply source, that remains

I:

Valve 6 * 9 open and the emergency air supply to air bearing 6 is interrupted by valve 71, which remains in its closed position. In this position, the valve 69 communicates with the line 77 via the line 73b and, together with each de-energized open valve 79 and the secondary line 80, forms a “ closed line circuit”. If the main air delivery then

i ■ i

is turned on, the valve 69 closes according to the pressure

i ■

! in line 70 and the air bearing is via line 63

jsupplied. The position of the valve 71 will not change, 'Ida the valve 75 in its deenergized and closed,

; I.

remains.

In this condition, provided that the correct pressures are in two lines 63 and 65 are made, the electrical switch 67, the one in series with the power source circuit to the main machine switch (not shown) is connected, closed so that when the main switch itself is closed, the chuck drive motor 25 is energized to set the chuck in circulation. Closing the main switch will also switch valve 75 excite and thus open, βο that the main air pressure over the Line 74 is applied to cylinder 71c, whereby the KoI-iben is moved and the valve is switched to its open position against the action of the spring 72, whereby the in dashed lines Lines shown connections 73a are made in the valve. In this position when the main air supply If it fails, the valve 69 will be opened and emergency air supply

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ORIGINAL INSPECTED

will flow through valve 69 and valve 71 to supply air bearing 6. The failure will continue to open switch 67 on line 63 which will then cut power to the main machine switch, causing the chuck drive motor

25 is switched off. The failure will also automatically return the transport arm 36 to its original retracted position and a brake (not shown) normally held in an inoperative state by main air pressure will apply to the chuck rim 23 to brake the chuck and from its full speed within from one to three minutes to stop. According to the interruption in the power supply, the valve 75 is de-energized and closed, However, the valve 71 is opened by the pressure of the emergency supply air held in its existing open position, with the emergency air supply via secondary line 80, the connections 73a and the secondary line 76 to the cylinder 71c flows.

If the engine stop signal during normal operation of the machine is given, the motor 25 is switched off, the valve 75 is de-energized and closed, and the valve 79 is instantaneous energized and closed, whereby the air supply to the cylinder 7lc via the branch line 76 is interrupted, whereby it the valve 71 is allowed to return to its original closed position. Ee facilities are provided to stop the pulsation of the valve 79, as described, when the engine stop signal 1st given, namely while the air bearing is being supplied with emergency air, until the motor 25 has come to a standstill at least is. In order to supply the emergency air supply to the main air via the

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To prevent secondary line 80, the main air pressure should be light below that of the emergency supply air, the air pressure will be the

j Emergency supply at the junction of the secondary line 80 with the line 77 by a regulator 61 to approximately 2.8 kp / cm ²

j, while the check valve 78 is limited to approximately 5.6 kp / cnr is unregulated.

From the above it can be seen that the safety circuit ensures that emergency air is automatically supplied to the air-bearing Chuck is supplied and «was immediate if partial or total failure of the main air supply during operation of the Machine occurs, but the safety circuit minimizes the amount of feed air required in all other circumstances. '

i;

According to the inertia of the chuck, -the minimum i Drag resistance of the air bearing 6 and the rotational speed of the

Chuck can continue for this when it is unbraked

several hours to rotleren if the drive belt 24 broke !should be. For this reason, devices (not shown) are provided to set a belt brake in motion and to apply automatically to the aforementioned brake on the outer edge of the chuck. This facility may include a circle that Includes fluid logic elements.

It should be stressed that various amendments will be made can without deviating from the concept of the invention. For example, the air bearing can be used without the advance mechanism described and illustrated and can be used with other types of

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Machine tools used or other suitable devices. The axis of rotation of the bearing can be other than vertical, for example horizontal or inclined _} and the bearing can be operated with a fluid other than air, for example with a liquid such as oil, or with gas. It should be emphasized that the term "fluid" includes flow media which are in the liquid or gaseous state.

The inclination of the opposing bearing surfaces 8 and 12 can be changed, and the bearing surfaces 11 and 13 can instead or run inclined in addition to the bearing surfaces 8 and 12 and the annular recess and the shoulder that goes through this

Bearing surfaces are formed to the "\ chuck support 4 and form corresponding to the chuck 5, instead of j reversed part in order to minimize the risk of placing or galling or other damage to the opposed bearing surfaces, these bearing surfaces should accidentally during the;. Rotation of the chuck come into contact, i some or all of the opposing bearing surfaces may be coated, coated or otherwise treated to reduce their coefficient of friction and / or reduce their wear resistance and / or increase their resistance to seizing the bearing surfaces can j be treated so that sulfur or a sulfur compound contained in \ penetrates the bearing surfaces, which can be done for example with a method that let developed by Imperial Chemical Industries! and ale method under the name "Cassell Sulphinuz" known 1st.

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Although the air bearing or the air-lubricated bearing of the chuck, that is specifically described is on the order of thirteen inches in diameter, the diameter may be also varied within the range of ten to sixteen inches will.

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Claims (8)

DR. HUGO WILCKEN DIPL.-ING. THOMAS WILCKEN 8.1.1971 Applicant: Caplin Engineering Company Limited, Ipswich (Suffolk) Hadleigh Road, Elton Park Works (UK) Claims M.) Cutting device, characterized in that the Cutting support member or the cutting support is mounted in a fluid-lubricated bearing for the purpose of rotation. 2. Apparatus according to claim 1, characterized in that the fluid-lubricated bearing is an air-lubricated one charged with compressed air Bearing is arranged between the cutting support and a carrier for the cutting support. 3. Apparatus according to claim 2, characterized in that the Cutting support is mounted for rotation about a generally vertical axis, the fluid-lubricated Bearing includes cooperating bearing surfaces which are formed by the cutting support and the carrier and after run divergent below and have the shape of a truncated cone. 4. Apparatus according to claim 3, characterized in that the fluid-lubricated bearing also cooperating bearing - 2 - 109819/13 " includes surfaces formed by the support and the carrier and which are generally horizontal and annular in shape, the working cycle during the Operation of the tool between the opposing frustoconical bearing surfaces and between the opposing ones horizontal bearing surfaces is on the order of 0.0279 mm. 5. Apparatus according to claim 4, characterized in that the i ■ ■ horizontal bearing surfaces of the cutting support and of the carrier are arranged above and below and above the frustoconical bearing surfaces in order to create a radially outwardly open annular recess in the cutting support . and form a cooperating annular shoulder extending radially inward from the carrier. 6. Apparatus according to claim 5, characterized in that the Carrier is provided with a compressed air charge line arrangement with a plurality of circumferentially distributed openings, the Exits to the horizontal and truncated cone-shaped bearing surfaces of the carrier, communicates, and that at the radial apex of the annular shoulder a plurality of circumferentially distributed Exits is provided, whereby pressurized air continuously through the during operation of the tool Vents flows to create a cushion of air between the collaborating To form storage areas and then from the outlets and in front of the edges or boundaries of the cooperating storage areas 109819/1332 to flow away. _f I 7. Device according to claims 1 to 6, characterized in that net that the cooperating bearing surfaces of the fluid-lubricated bearing are coated or otherwise treated to reduce the risk of damage to the bearing surfaces
due to erroneous engagement of the bearing surfaces with one another
decrease during the rotation of the carrier. 8. Device according to claims 1 to 7, characterized in that it is a main source of pressurized fluid
for normal operation of the fluid-lubricated bearing! and in that it includes a pressurized _{Notversorgungsquelle:} .stehendem fluid and a safety arrangement includes, soft latter adapted automatically under pressure
Fluid from the emergency supply source eu the fluid-lubricated
To deliver bearings, namely after failure of the fluid delivery of
the main source, and that the arrangement for decelerating or braking the rotation of the cutting support is adapted. 109819/1332